37 CFR 1.56 (Rule 56) establishes that there is a duty to disclose information to the Patent Office. The regulation states that “[e]ach individual associated with the filing and prosecution of a patent application has a duty of candor and good faith in dealing with the Office, which includes a duty to disclose to the Office all information known to that individual to be material to patentability.” The failure to disclose information could result in a later ruling of inequitable conduct and an invalidation of the patent.

In 1998 the Federal Circuit wrote, “inequitable conduct resides in failure to disclose material information… with an intent to deceive.” It is clear that inequitable conduct is made up of two distinct elements and they are: (1) intent; and (2) materiality. These two elements must each be proven by clear and convincing evidence.

Relationship of Office Actions to the Duty to Disclose

A recent question that has been debated among patent prosecutors is whether the duty to disclose material information extends to a duty to disclose the contents of previous office actions from related and/or unrelated patent prosecutions. More practically, patent prosecutors are worried that if they make a decision not to disclose the contents of a previous office action, that failure to disclose will later be used in an allegation of inequitable conduct that could invalidate the patent.

An office action is a response from the examiner at the United States Patent and Trademark Office to a filing by a patent prosecutor in the course of prosecuting a patent. An office action can be an allowance of the claims, a rejection of the claims pursuant to substantive patentability rules, or an objection to the claims pursuant to procedural rules. By its very nature, an office action merely represents the opinions and conclusions of the examiner who sent it and that examiner’s subjective interpretation of patent law and procedure. It is therefore unclear whether office actions fit within the definition of material information.

To answer the question whether office actions must be disclosed, it is therefore necessary to investigate the meaning of “material information” as it is set forth in Rule 56 to determine the extent of the materiality prong of the inequitable conduct test.

Material Information

Is an office action “information”?

Prior to determining whether an office action is material information, it must be determined whether it is information in the first place. As stated above, an office action represents the opinions and conclusions of an examiner at the USPTO based on the facts, arguments, and assertions put forth by the applicant in the patent application and in the prosecution history. It is possible that this definition does not bring office actions within the meaning of information, such that a categorical rule that they need not be disclosed can be established.

However, the language of the regulation and the Manual of Patent Examining Procedure (MPEP) suggests that such a narrow reading of the word “information” should not be endorsed. Rule 56 states that “all information” must be disclosed and it is therefore clear that the regulation is not referring to only prior art. The MPEP says that “the term “information” in Rule 56(a) is intended to be all encompassing.” The MPEP specifically mentions that all information must be disclosed, “regardless of the source.” There is a duty to disclose “information… as to other co-pending United States applications which are “material to patentability.”

The fact that neither the regulation nor the MPEP go into great detail about the meaning of “information” seems to indicate a broad definition of information, particularly when it is modified by the word “all.” This suggests that the “information” requirement will not provide an easy categorical rule as to whether office actions from other patent prosecutions need be disclosed. Rather, an office action from a different patent prosecution probably fits within the meaning of “information” and therefore its materiality must be analyzed in the same way as the materiality of any other information for which there may be a duty to disclose.

Materiality

Once it is established that an office action fits within the meaning of information, the entire disclosure question stems from the definition of materiality provided by the regulation. Rule 56(b) says that information is only material “it is not cumulative to information already of record or being made of record in the application, and (1) [i]t establishes, by itself or in combination with other information, a prima facie case of unpatentability of a claim; or 2) [i]t refutes, or is inconsistent with, a position the applicant takes in: (i) [o]pposing an argument of unpatentability relied on by the Office, or (ii) [a]sserting an argument of patentability.

There are two aspects to the materiality question, which can be referred to as timing and substance. With regard to timing, information is only material if it is not cumulative to information already of record. This means that regardless of the substantive nature of the information, if it has already been disclosed (or at least a way of obtaining it has been disclosed) then there is no duty to disclose it.

Not surprisingly, the majority of the focus of the case law has tended to be about the substantive materiality question addressed in Rule 56(1) and the standard has evolved over time. Early doctrine regarding materiality of information involved three tests that the court laid out in In re Multidistrict Litigation Involving Frost Patent. There was an objective ‘but for’ test, a subjective ‘but for’ test, and a ‘but it may have test’.[1]

More recently, there are two different tests that the CAFC has used in determining whether information is material. Prior to 1992, the courts used a reasonable examiner test, asking whether a reasonable examiner would have deemed the information material. This was based on the language of Rule 56 prior to its being changed in 1992.

In 1992, the language of Rule 56 was amended to its current form, involving a prima facie case of unpatentability. It appeared that the reasonable examiner test was no longer pertinent. However, recently, the court in Digital Control, Inc. v. The Charles Machine Works suggested that the reasonable examiner test was still alive and the prima facie test provides an additional test of materiality.

Is an office action “material”?

Cumulativeness

It is possible that the timing aspect of at least some types of office actions makes them inherently cumulative to information already of record such that the substantive question of materiality need not be addressed. With regard to cumulativeness, it should be noted that there is a potential difference between office actions from parent applications of the application at issue and office actions from unrelated applications. It is likely that in a regular patent application, office actions from other unrelated patent applications fit within the rule and qualify as information known to the individual and they are not cumulative to information already of record. Therefore, because office actions from other unrelated applications are not of record in the present application, there may be a requirement to disclose them, depending on their substantive materiality.

With regard to the question of disclosure in continuing applications of office actions from parent applications and other related applications, it is more questionable whether office actions are not cumulative. MPEP 609.02 says that it is “not necessary for the applicant to submit an information disclosure statement in the continuing application that lists the prior art cited by the examiner in the parent application” and that “the examiner of the continuing application will consider information which has been considered by the Office in the parent application.” Therefore, in the filing of a continuing application, it would appear that the office actions are cumulative to information already of record and the substantive question of materiality need not be addressed.

However, recently, the court in Larson Mfg. Co. of South Dakota, Inc. v. Aluminart Products Ltd.said that office actions from related co-pending patent applications can be material to prosecution. The court emphasized that the knowledge of a potentially different interpretation is clearly information that an examiner would want to have and therefore is material. Therefore, it is important to note that the court seemed to endorse the reasonable examiner test that was kept alive by the Digital Control court and the court seemed to somewhat merge the timing/substance questions in evaluating the materiality of office actions.

It therefore seems apparent that no categorical rule can be derived either with respect to unrelated office actions or with respect to related office actions based on their cumulativeness. Thus, with regard to the question of whether office actions must be disclosed to the PTO, it depends on an evaluation of the substantive nature of the information contained in the office action.

The substantive aspect of office actions

Assuming that the relevant materiality question is whether information creates a prima facie case of unpatentability and that the question of whether a reasonable examiner would want to have the information is still relevant, it seems that there is a requirement to disclose the contents of office actions.

Under the reasonable examiner test, which is still relevant according to the Digital Control court, a reasonable examiner would want to know about office actions from other patent prosecutions and to know about other examiners’ views on the subject matter. With regard to the language of the current Rule 56, an examiner’s opinions and conclusions based on the application, the prosecution history, and the prior art is probably enough to establish a prima facie case of unpatentability.

Furthermore, in 1992 the Federal Circuit in LaBounty Mfg v. U.S. Int’l Trade Comm’nestablished that there is a duty to err on the side of disclosure in ‘close cases.’ Essentially, when in doubt about whether the information should be disclosed, it is not simply a recommendation that the disclosure should be made but rather there is a duty to disclose. Additionally, disclosing earlier office actions from other prosecution can be used in subsequent litigation to show good faith and negate deceptive intent.

Conclusion

All of this doctrine seems to suggest that there is nothing unique about office actions with respect to the duty to disclose. Office actions are information. They are not necessarily cumulative to information already of record, even in cases of continuing applications. The fact that they consist of an examiner’s opinions and conclusions does not inherently mean that they cannot establish a prima facie case of unpatentability pursuant to Rule 56(1). Therefore, the materiality of previous office actions must be analyzed exactly the same way as all other information with respect to the duty to disclose.